Unless your router is literally on top of your central air unit (which is OUTSIDE), I can't see it blocking WiFi. To me, it sounds like you called one of the big telecoms and they're making excuses for the shitty hardware they use. I've heard every excuse under the sun: fish tanks, light fixtures, pyrite, etc, etc.

I happen to have that router and it does seem to have poor signal strength depending on how far or what it has to go through. I'm in a basement apartment and I get about 1 or 2 bars signal from my living room to my master bedroom. I eventually plan to switch it out (when it dies).

I am the Big ISP company LOL Im a Tech for Rogers Cable Here In the GTA area.

I didnt think it could happen, But RF Bands are RF Bands.

I had a Service call to a house for the same issue, Dropping Wifi. It would happen at the same time every night.
The only thing that came on at that time was a Jet pump for the hot tube.
Turned off the pump for a few days, Wifi worked like a charm.

Everytime the AC kicks in, I drop 2-3 bars and 3 out of 10 times drop my signal.

I have also seen alot of 655s dropping WIFI signal, So is it time to upgrade? Or no point.

I would say anything and that is the AC and Hot Tub both share one thing in common... HUGEEEEEEEEEEEE draw of power when they both kick in and this could perhaps cause a drop in power voltage to the home and the router is getting the worst of it causing it to drop off.

The home can probably -- assuming reasonable loads for the age of the build -- handle the AC and router at the same time. However, they might be on the same circuit. Maybe spend some time flipping breakers to see if that's the case.

If it's not a new home, the wiring wasn't really designed for multiple high-draw electronics to be plugged in on the same circuit. If it's a new home, well, you can easily find builders who put too many items on a circuit.

I would put money on it being the initial power draw when the AC/hot tub kick on. Why do I say this? Because of what I see with my portable AC. When it kicks on my UPS kicks in for a quick moment. Yes I have it set very sensitive so it is not really losing power but definitely causing ruckus with the power in my place. It is the same thing with my laser printer as well. So really if someone is noticing a drop/loss in signal right when the AC turns on it is power causing the issue.

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